| Cashes Green Estate Management Board Limited | Real estate | 2013 |
| Cashflow Castle Limited | Wholesale & retail | 2023 |
| Cashflow Solutions UK Ltd | Financial services | 2009 |
| Cask Vault Limited | Wholesale & retail | 2025 |
| Casselle Cosmetics Ltd | Other services | 2025 |
| Cassius Clay Limited | Financial services | 2022 |
| Cassra LLP | | 2012 |
| Castelluccio Ltd | Hospitality | 2021 |
| Casterbridge Lessees Limited | Households | 1999 |
| Castle Acre Stores Limited | Wholesale & retail | 2022 |
| Castle Close (Sunbury on Thames) Limited | Households | 1991 |
| Castle Hill Fire Doors Limited | Construction | 2004 |
| Castle Hill Fire Protection Limited | Construction | 2013 |
| Castle Mews (Shrewsbury) Management Company Limited | Households | 2002 |
| Castlecroft Stores Limited | Administrative & support | 2003 |
| Castleknock Limited | Real estate | 2024 |
| Castletown Properties Management Limited | Real estate | 2021 |
| Castleview Investments Limited | Real estate | 2002 |
| Cat Action Trust Shops Limited | Other services | 2013 |
| Catalis Development Services Limited | Professional & scientific | 2006 |
| Catalis Group Limited | Extraterritorial | 1998 |
| Catalyst Care Limited | Health & social care | 2020 |
| Catalyst Casa Ltd | Real estate | 2023 |
| Catch and Cook Limited | Wholesale & retail | 2025 |
| Catchy Concepts Ltd | Wholesale & retail | 2019 |
| Cate Anderson Copywriter Ltd | Administrative & support | 2017 |
| Caterfix Pro Limited | Manufacturing | 2025 |
| Catersales Construction Ltd | Construction | 2023 |
| Catgm Global Ltd | Manufacturing | 2026 |
| Catgm Holding Ltd | Financial services | 2026 |
| Cathay Composites Limited | Wholesale & retail | 1973 |
| Cathay Investments 2 Limited | Professional & scientific | 2010 |
| Cathay Investments 2 Properties Limited | Real estate | 2015 |
| Cathay Investments 3 Limited | Administrative & support | 2018 |
| Cathay Investments 4 Limited | Administrative & support | 2020 |
| Cathay Investments 5 Limited | Administrative & support | 2020 |
| Cathay Investments 6 Limited | Administrative & support | 2020 |
| Cathay Investments Limited | Professional & scientific | 2003 |
| Cathect Project Management Ltd | Professional & scientific | 2016 |
| Cathedral Walk (Wells) Management Company Limited | Households | 2013 |
| Catherine Ahonsi Services Limited | Health & social care | 2023 |
| Catherine Asare Limited | Health & social care | 2022 |
| Caulcrick Technical Services Limited | Information & communication | 2024 |
| Causatica Ltd | Information & communication | 2025 |
| Cautley Properties Limited | Construction | 2014 |
| Cavalier Court (Teddington) Management Company Limited | Households | 2003 |
| Cavendish Court (Gillingham) Management Limited | Households | 2021 |
| Cavendish Grange (Warlingham) Management Company Limited | Households | 2020 |
| Cavendish Lodge (Bath) Management Company Limited | Households | 1997 |
| Cavendish ROW Limited | Wholesale & retail | 2025 |
| Caxton Court (Bath) Limited | Households | 2000 |
| Caxton Gate Limited | Households | 1987 |
| Caylx Limited | Hospitality | 2009 |
| Caysh | Health & social care | 1993 |
| Caysh Enterprise CIC | Administrative & support | 2013 |
| Cazel Limited | Information & communication | 2021 |
| CB & SS Limited | Real estate | 2017 |
| CB Fitness Marketing Limited | Arts & recreation | 2025 |
| CB Heating & Plumbing Limited | Construction | 2018 |
| CB Motor Autos Ltd | Professional & scientific | 2026 |
| Cb&Aa Ltd | Administrative & support | 2025 |
| CBD Hemp Ltd | Wholesale & retail | 2018 |
| CBE Centre Limited | Education | 2026 |
| CBM Fitness Limited | Arts & recreation | 2025 |
| CBV (Business Centre) Limited | Administrative & support | 1989 |
| CC Actuarial Limited | Professional & scientific | 2016 |
| CC Ckma Group Limited | Financial services | 2025 |
| CC Consultancy Coaching Ltd | Professional & scientific | 2007 |
| CC Group Services Limited | Financial services | 2017 |
| CC Logistic Global Ltd | Wholesale & retail | 2022 |
| CC London Kitchen Ltd | Hospitality | 2026 |
| CC Refurbishment Ltd | Construction | 2016 |
| CC Valet Ltd | Administrative & support | 2023 |
| CC Vbps Group Limited | Financial services | 2025 |
| CC Window Cleaning Ltd | Administrative & support | 2018 |
| CC35 Management Company Ltd | Households | 2004 |
| CCA Environmental Limited | Professional & scientific | 2005 |
| Cceze Ltd | Information & communication | 2015 |
| Ccha Developments Limited | Construction | 2018 |
| CCM Settlement Holdings Ltd | Financial services | 2022 |
| CCM Settlement Ltd | Financial services | 2013 |
| CCP Pumps Ltd | Manufacturing | 2018 |
| Ccrate Place Limited | Real estate | 2025 |
| CCS Group Holdings Limited | Administrative & support | 2015 |
| CD Consultancy Limited | Arts & recreation | 2020 |
| CDC Enterprise Limited | Real estate | 1969 |
| CDF London Ltd | Hospitality | 2017 |
| CDH Risk Management Limited | Professional & scientific | 2014 |
| Cdjf Limited | Wholesale & retail | 2016 |
| CDL (1992) Company Limited | Professional & scientific | 2018 |
| CDS Electrical Installs Ltd | Construction | 2026 |
| CDS Plus Ltd | Other services | 2013 |
| CDS Projects Limited | Professional & scientific | 2014 |
| Ceara Claims Ltd | Wholesale & retail | 2020 |
| Cedar Court (Cheltenham) Residents Association Limited | Households | 1985 |
| Cedar House (Purley) Management Company Limited | Households | 2013 |
| Cedar Tree London Limited | Real estate | 2021 |
| Cedarhall UK Limited | Real estate | 2016 |
| Cedars House Ltd | Hospitality | 2010 |
| Cedars View (Mickle Trafford) Management Company Limited | Households | 2012 |